From: Carnegie, Australia
It is an average..
Leader name and his average skill will be visible in the unit info box below the counter image. Leader rank, full name, his average skill and victory:defeat ratio will be visible in hex tooltip. Average skill is equal to the average of morale, admin, initiative, mech and infantry skills for land leaders, and to the average of morale, admin, initiative and air skills for air leaders
Apparently visiting a museum to inspect a Valentine tank is NOT romantic.